ok if its for turn then you can have the Tool number persistant but the offsets will not be kept. This is because Tool 1 can have many offsets, eg T0101, T0111, T0121  etc etc.
 It is best practice to have the last part of any G Code indexing back to T0101 before it ends, that way you always know that after a reset Mach has the correct offsets loaded.
 If however you did have  Tool 3 In position the DRO  would show it was tool3 but the offset would be zero, ie T0300. If however you called the correct tool and offset in your code it would again be set to the correct offset.

Hood

All the better reason to think and RETHINK this stuff out before you commit to ANY wiring

Wayne.....

I have to agree with Wayne, much easier doing a bit of wiring than it is to stitch a finger back on.
Hood

Or less severe than physical injury, just designing yourself into a corner.   Done it myself many times!   Makes you think more about possible scenarios in subsequent projects

Myown lathe is almost constantly on my mind at the moment,  Maybe I'll start dreaming solutions soon haha....

Wayne...

4 months of thinking. Complete lathe, no retrofit.
Almost done ... Only left is the door issue and to see the spindle accelerate and decelerate as I am going in direction of X-- and X++. And, of course, all other thinks that I left behind, I hope very few. Still coolant protection of ballscrew in my X axis is still killing me, but I will think in it after it runs.

And Hood, the ideia of always end with the same tool is a very good one.
I will implement that one, since I also made the software that generate the Gcode that the machine will use.
Nice one, and easy too.

You could easily create an interlock to do what you want, using just a relay with it's contacts in series with the spindle start output in Mach   Coil to be operated by the door switch.

Same relay with enough poles could put mach into Feedhold.

Probably better to do that than rely on software alone.


Wayne....

I'm not sure that will do what he wants.  When you press FeedHold, it will still take a second or two for the machine to stop.  If you simply shut off the spindle while the machine is still moving, you stand a good chance of losing position and/or breaking a tool and/or damaging the work.  I don't think you can turn off the spindle until you're sure movement has stopped.

Regards,
Ray L.

There is a setting in Mach to lift the tool when stop is pressed, obviously Stop doesnt want to get pressed until a feedhold has been done so maybe its not a good idea either.
Best option may be to have a lockpin hold the door shut until a feedhold has been done and the spindle has stopped.
Hood

For sure this is the best option. Also the user should be aware only to "pause" the system when it is not cutting, this is, when it is outside the cutting part.

There is a setting in Mach to lift the tool when stop is pressed, obviously Stop doesnt want to get pressed until a feedhold has been done so maybe its not a good idea either.
Best option may be to have a lockpin hold the door shut until a feedhold has been done and the spindle has stopped.
Hood